chore(release): update version in master to v0.14.0+git
Merge pull request #2233 from mboersma/bump-v014+git

chore(release): update version in master to v0.14.0+git
ref(user-data): "make discovery-url" copies from user-data.example

This also adds contrib/coreos/user-data to .gitignore, so that local
changes to this essential file do not cause "git status" to mark the
repo as dirty.